scholarly journals HDAC Inhibitor Abrogates LTA−Induced PAI-1 Expression in Pleural Mesothelial Cells and Attenuates Experimental Pleural Fibrosis

2021 ◽  
Vol 14 (6) ◽  
pp. 585
Author(s):  
Wei-Lin Chen ◽  
Mei-Chuan Chen ◽  
Shang-Fu Hsu ◽  
Shih-Hsin Hsiao ◽  
Chi-Li Chung

Lipoteichoic acid (LTA) stimulates pleural mesothelial cell (PMC) to overproduce plasminogen activator inhibitor-1 (PAI-1), and thus may promote pleural fibrosis in Gram-positive bacteria (GPB) parapneumonic effusion (PPE). Histone deacetylase inhibitor (HDACi) was found to possess anti-fibrotic properties. However, the effects of HDACi on pleural fibrosis remain unclear. The effusion PAI-1 was measured among 64 patients with GPB PPE. Pleural fibrosis was measured as radiographical residual pleural thickening (RPT) and opacity at a 12-month follow-up. The LTA−stimulated human PMCs and intrapleural doxycycline−injected rats were pretreated with or without the pan-HDACi, m-carboxycinnamic acid bis-hydroxamide (CBHA), then PAI-1 and collagen expression and activated signalings in PMCs, and morphologic pleural changes in rats were measured. Effusion PAI-1 levels were significantly higher in GPB PPE patients with RPT > 10 mm (n = 26) than those without (n = 38), and had positive correlation with pleural fibrosis shadowing. CBHA significantly reduced LTA−induced PAI-1 and collagen expression via inhibition of JNK, and decreased PAI-1 promoter activity and mRNA levels in PMCs. Furthermore, in doxycycline−treated rats, CBHA substantially repressed PAI-1 and collagen synthesis in pleural mesothelium and minimized pleural fibrosis. Conclusively, CBHA abrogates LTA−induced PAI-1 and collagen expression in PMCs and attenuates experimental pleural fibrosis. PAI-1 inhibition by HDACi may confer potential therapy for pleural fibrosis.

2019 ◽  
Vol 20 (20) ◽  
pp. 5076
Author(s):  
Cheng-Ying Hsieh ◽  
Joen-Rong Sheu ◽  
Chih-Hao Yang ◽  
Wei-Lin Chen ◽  
Jie-Heng Tsai ◽  
...  

Thrombin is an essential procoagulant and profibrotic mediator. However, its implication in tuberculous pleural effusion (TBPE) remains unknown. The effusion thrombin and plasminogen activator inhibitor-1 (PAI-1) levels were measured among transudative pleural effusion (TPE, n = 22) and TBPE (n = 24) patients. Pleural fibrosis, identified as radiological residual pleural thickening (RPT) and shadowing, was measured at 12-month follow-up. Moreover, in vivo and in vitro effects of thrombin on PAI-1 expression and mesothelial–mesenchymal transition (MMT) were assessed. We demonstrated the effusion thrombin levels were significantly higher in TBPE than TPE, especially greater in TBPE patients with RPT > 10mm than those without, and correlated positively with PAI-1 and pleural fibrosis area. In carbon black/bleomycin-treated mice, knockdown of protease-activated receptor-1 (PAR-1) markedly downregulated α-smooth muscle actin (α-SMA) and fibronectin, and attenuated pleural fibrosis. In pleural mesothelial cells (PMCs), thrombin concentration-dependently increased PAI-1, α-SMA, and collagen I expression. Specifically, Mycobacterium tuberculosis H37Ra (MTBRa) induced thrombin production by PMCs via upregulating tissue factor and prothrombin, and PAR-1 silencing considerably abrogated MTBRa−stimulated PAI-1 expression and MMT. Consistently, prothrombin/PAR-1 expression was evident in the pleural mesothelium of TBPE patients. Conclusively, thrombin upregulates PAI-1 and MMT and may contribute to tuberculous pleural fibrosis. Thrombin/PAR-1 inhibition may confer potential therapy for pleural fibrosis.


2003 ◽  
Vol 89 (05) ◽  
pp. 926-935 ◽  
Author(s):  
Utta Berchner-Pfannschmidt ◽  
Christoph Wotzlaw ◽  
Robbert Cool ◽  
Joachim Fandrey ◽  
Helmut Acker ◽  
...  

SummaryThe hypoxia-inducible transcription factor HIF-1 mediates upregulation of plasminogen activator inhibitor-1 (PAI-1) expression under hypoxia. Reactive oxygen species (ROS) have also been implicated in PAI-1 gene expression. However, the role of ROS in HIF-1-mediated regulation of PAI-1 is not clear. We therefore investigated the role of the GTPase Rac1 which modulates ROS production in the pathway leading to HIF-1 and PAI-1 induction.Overexpression of constitutively activated (RacG12V) or dominant-negative (RacT17N) Rac1 increased or decreased, respectively, ROS production. In RacG12V-expressing cells, PAI-1 mRNA levels as well as HIF-1α nuclear presence were reduced under normoxia and hypoxia whereas expression of RacT17N resulted in opposite effects. Treatment with the antioxidant pyrrolidinedithiocarbamate or coexpression of the redox factor-1 restored HIF-1 and PAI-1 promoter activity in RacG12V-cells. In contrast, NFκB activation was enhanced in RacG12V-cells, but abolished by RacT17N. Thus, these findings suggest a mechanism explaining modified fibrinolysis and tissue remodeling in an oxidized environment.


2014 ◽  
Vol 2014 ◽  
pp. 1-12 ◽  
Author(s):  
Zhong-Hui Wang ◽  
Wei-Ying Ren ◽  
Lei Zhu ◽  
Li-Juan Hu

Background. The mechanisms by which plasminogen activator inhibitor-1 (PAI-1) regulates inflammation, especially in acute respiratory distress syndrome (ARDS), are largely unknown.Objective. To assess the relationship between PAI-1 and autophagy in inflammatory reactions induced by LPS in rat NR8383 cells.Methods. ELISA was used to assess the amounts of TNF-α, IL-1β, and PAI-1 in cell culture supernatants; TLR4, MyD88, PAI-1, LC3, Beclin1, and mTOR protein and mRNA levels were determined by western blot and quantitative RT-PCR, respectively; western blot was used to determine NF-κB protein levels. To further evaluate the role of PAI-1, the PAI-1 gene was downregulated and overexpressed using the siRNA transfection technology and the pCDH-PAI-1, respectively. Finally, the GFP Positive Expression Rate Method was used to determine the rate of GFP-LC3 positive NR8383 cells.Results. In LPS-induced NR8383 cells, TNF-α, IL-1β, and PAI-1 expression levels increased remarkably. Upon PAI-1 knockdown, TNF-α, IL-1β, PAI-1, TLR4, MyD88, NF-κB, LC3, and Beclin1 levels were decreased, while mTOR increased. Conversely, overexpression of PAI-1 resulted in increased amounts of TNF-α, IL-1β, PAI-1, TLR4, MyD88, NF-κB, LC3, and Beclin1. However, no significant change was observed in mTOR expression.Conclusions.In NR8383 cells, PAI-1 contributes in the regulation of LPS-induced inflammation, likely by promoting autophagy.


2000 ◽  
Vol 84 (07) ◽  
pp. 59-64 ◽  
Author(s):  
Luciana Mussoni ◽  
Cristina Banfi ◽  
Luigi Sironi ◽  
Magda Arpaia ◽  
Elena Tremoli

SummaryThe effects of fluvastatin, a synthetic hydroxymethylglutaryl coenzyme A (HMG-CoA) inhibitor, on the biosynthesis of tissue plasminogen activator (t-PA) and of its major physiological inhibitor (plasminogen activator inhibitor type 1, PAI-1) were investigated in cultured human umbilical vein endothelial cells (HUVEC). Fluvastatin (0.1 to 2.5 µM), concentration-dependently reduced the release of PAI-1 antigen by unstimulated HUVEC, subsequent to a reduction in PAI-1 steady-state mRNA levels and de novo protein synthesis. In contrast, it increased t-PA secretion.The drug also reduced PAI-1 antigen secreted in response to 10 µg/ml bacterial lipopolysaccharide (LPS), 100 U/ml tumour necrosis factor α (TNFα) or 0.1 µM phorbol myristate acetate (PMA).Mevalonate (100 µM), a precursor of isoprenoids, added to cells simultaneously with fluvastatin, suppressed the effect of the drug on PAI-1 both in unstimulated and stimulated cells as well as on t-PA antigen. Among intermediates of the isoprenoid pathway, all-trans-geranylgeraniol (5 µM) but not farnesol (10 µM) prevented the effect of 2.5 µM fluvastatin on PAI-1 antigen, which suggests that the former intermediate of the isoprenoid synthesis is responsible for the observed effects.


1989 ◽  
Vol 62 (02) ◽  
pp. 723-728 ◽  
Author(s):  
T Kooistra ◽  
P J Bosma ◽  
H A M Töns ◽  
A P van den Berg ◽  
P Meyer ◽  
...  

SummaryClinical studies have shown that plasma insulin levels are closely related to plasma plasminogen activator inhibitor 1 (PAI-1) levels. To investigate a possible involvement of hepatocytes we have studied the effect of insulin on PAI-1 production by primary cultures of human hepatocytes. We have isolated human hepatocytes from seven left liver lobes. PAI-1 activity measured in 24 hours conditioned medium varied considerably between the various hepatocyte preparations (from 2.9 to 8.5 units per 5 cm2of cells) possibly as a result of interindividual variability in basal PAI-1 production by hepatocytes from different donors. In all cases, however, the relative extent, time profile and dose-dependency of the insulin-induced increase in PAI-1 synthesis were consistent. Up to about 7 nM, insulin dose-dependently increased both PAI-1 activity and PAI-1 antigen production. The increase in PAI-1 synthesis became measurable between 4 and 8 hours after addition of the hormone, and maximally reached twofold control values. The increase in PAI-1 synthesis could be fully explained by a concomitant increase in PAI-1 mRNA levels. The effect of insulin seems fairly specific for the synthesis of PAI-1: overall protein synthesis and mRNA levels of some control proteins (albumin and fibrinogen) did not markedly change after insulin addition. These results, obtained with primary cultures of human hepatocytes, are fully comparable with those obtained with the hepatocellular carcinoma cell line Hep G2. They strengthen the suggestion that the elevated level of PAI-1 in high insulin plasma might be the result of increased hepatic synthesis of PAI-1.


2007 ◽  
Vol 98 (10) ◽  
pp. 864-870 ◽  
Author(s):  
Katsutaka Oishi ◽  
Naoki Ohkura ◽  
Juzo Matsuda ◽  
Norio Ishida

SummaryRelationships between energy intake and fibrinolytic functions have been documented in detail. We evaluated food deprivation (FD) as a means of modulating fibrinolytic activity in genetically obese and diabetic db/db mice and in their lean counterparts. Twelve hours of FD induced considerable gene expression of plasminogen activator inhibitor-1 (PAI-1) in both epididymal (3.8-fold, p<0.05) and intestinal (2.4-fold, p<0.05) adipose tissues without affecting plasma PAI-1 levels in db/db mice, whereas the FD did not affect these parameters in wild-type mice. Importantly, 24 hours of FD increased the plasma PAI-1 content in wild-type (1.9-fold, p<0.01) but not in db/db mice, although adipose PAI-1 mRNA levels were significantly increased in db/db mice. The plasma PAI-1 content significantly correlated with hepatic PAI-1 mRNA levels in wild-type (r=0.84, p<0.01) and in db/db (r=0.63, p<0.01) mice. However, plasma PAI-1 did not correlate with adipose PAI-1 expression in db/db mice, although adipose tissue in general is thought to be the principal site of PAI-1 production in obesity. Hepatic PAI-1 expression was closely correlated with serum levels of free fatty acids in wild-type (r=0.72, p<0.01), but not in db/db mice. Adipose PAI-1 expression significantly correlated with serum corticosterone levels in both genotypes (wild-type, r=0.52, p<0.05; db/db, r=0.51, p<0.01), suggesting that adipose PAI-1 expression is up-regulated by fastinginduced glucocorticoids. The present findings suggested that fasting differentially affects fibrinolytic activity in obese and lean subjects and that PAI-1 expression in the liver as well as in adipose tissues comprises an important determinant of increased risk for cardiovascular disease in obesity.


1988 ◽  
Vol 60 (01) ◽  
pp. 063-067 ◽  
Author(s):  
E A van den Berg ◽  
E D Sprengers ◽  
M Jaye ◽  
W Burgess ◽  
T Maciag ◽  
...  

SummaryThe plasminogen activator inhibitor (PAI-1) from endothelial cells is a potentially important regulator of plasminogen activator activity. Cultured human endothelial cells increase their PAI-1 production upon stimulation with LPS and TNF, agents that are known to cause an increase in PAI-1 levels in vivo.We isolated a PAI-1 cDNA probe, and by RNA hybridization analysis studied the regulation of PAI-1 mRNA synthesis in human endothelial artery cells. Freshly isolated endothelial cells do not contain detectable amounts of PAI-1 mRNA, but after adherence and incubation for 18 h in growth medium produce considerable amounts of PAI-1 activity and contain PAI-1 mRNA levels comparable to those found in subcultured cells. When subcultured endothelial cells are incubated for 6 h with LPS or TNF, both species of PAI-1 mRNA increase 10 to 20 fold, while PAI-1 activity in the growth medium increases only 1.5 to 2 fold. Stimulation of endothelial cells in the presence of cycloheximide (CHX) results in superinduction of mainly the 3.0 kb PAI-1 mRNA. The 3' end of this mRNA contains a 60 bp AT-rich sequence, that resembles 3' sequences present in a number of other genes superinducible with CHX.


2003 ◽  
Vol 89 (04) ◽  
pp. 666-673 ◽  
Author(s):  
Kurt Jungermann ◽  
Agnes Görlach ◽  
Thomas Kietzmann

SummaryMitogen-activated protein kinases (MAPKs) and protein kinase B (PKB) mediate growth and stress signals and have been implicated in the hypoxic response. Under hypoxic conditions, the expression of plasminogen activator inhibitor-1 (PAI-1) is mainly controlled by the hypoxia-inducible factor HIF-1. However, the role of MAPKs and PKB in HIF-1-mediated PAI-1 regulation is not clear.Treatment with the p38 inhibitor SB203580 and the PI3K inhibitor LY294002, but not with the MEK1 inhibitor PD98059, abrogated hypoxia-dependent PAI-1 induction in HepG2 cells. Consistently, overexpression of PKB or of the p38 upstream kinases MKK6 and MKK3 and of JNK, but not of ERK, enhanced PAI-1 mRNA levels. In MKK3-,MKK6- and PKB-expressing cells luciferase (Luc) activities from a hypoxia-inducible PAI-1-Luc construct or from a HIF-dependent Luc construct and, concomitantly, HIF-1α protein levels were enhanced. These findings indicate that p38- and PKB-dependent signalling pathways contribute to enhanced PAI-1 levels in the hypoxic response.Theme paper: Part of this paper was originally presented at the joint meetings of the 16th International Congress of the International Society of Fibrinolysis and Proteolysis (ISFP) and the 17th International Fibrinogen Workshop of the International Fibrinogen Research Society (IFRS) held in Munich, Germany, September, 2002.


2000 ◽  
Vol 279 (4) ◽  
pp. L707-L715 ◽  
Author(s):  
Maureen R. Horton ◽  
Mitchell A. Olman ◽  
Clare Bao ◽  
Kimberly E. White ◽  
Augustine M. K. Choi ◽  
...  

Pulmonary inflammation and fibrosis are characterized by increased turnover and production of the extracellular matrix as well as an impairment of lung fibrinolytic activity. Although fragments of the extracellular matrix component hyaluronan induce macrophage production of inflammatory mediators, the effect of hyaluronan on the fibrinolytic mediators plasminogen activator inhibitor (PAI)-1 and urokinase-type plasminogen activator (uPA) is unknown. This study demonstrates that hyaluronan fragments augment steady-state mRNA, protein, and inhibitory activity of PAI-1 as well as diminish the baseline levels of uPA mRNA and inhibit uPA activity in an alveolar macrophage cell line. Hyaluronan fragments alter macrophage expression of PAI-1 and uPA at the level of gene transcription. Similarly, hyaluronan fragments augment PAI-1 and diminish uPA mRNA levels in freshly isolated inflammatory alveolar macrophages from bleomycin-treated rats. These data suggest that hyaluronan fragments influence alveolar macrophage expression of PAI-1 and uPA and may be a mechanism for regulating fibrinolytic activity during lung inflammation.


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